The race is on for a Covid-19 vaccine, but the pace is less hare and more tortoise. And necessarily so: Developing a vaccine that’s both effective and safe is grueling, methodical work.
“When experts optimistically say that they expect a Covid-19 vaccine by the end of 2020, they’re talking about an emergency use authorized vaccine, not a fully-approved one,” says Dr. Seema Yasmin, director of the Stanford Health Communication Initiative.
No one can say for sure when a Covid-19 vaccine might arrive, because vaccine development is broken into several stages, each with a highly variable timeline. “But here’s a comparison,” Yasmin says. “The fastest vaccine we previously developed was for mumps, and that took four years to develop. And typically it takes 10 to 15 years to develop a vaccine. So 12 to 18 months would be record-breaking.”
Now, about those stages. The first is the exploratory phase, in which drug companies tinker with different approaches. With Covid-19, for instance, some drugmakers are trying to develop a nucleotide-based vaccine, which uses the virus’s genetic code instead of its proteins. Typically, the exploratory phase could take two to fo